The WO patent 03/066435 concerns a method for enhancing the cooking performance of microwave interactive packaging material comprising closed cells. Under the influence of the microwave field, these closed cells inflate and therefore bring the susceptor layer in closer contact to the food product. The problem with such a solution is that it is not possible to guarantee a continuous contact with the food product, because of the non flat surface of the inflated cells; the susceptor is therefore not fully in contact with the food product. Furthermore, the composition of the overall packaging material of this patent is complex and is composed of several layers, which finally leads to an expensive solution. The U.S. Pat. No. 4,985,300 concerns a heat shrinkable film useful for packaging for cooking a food product in a microwave oven. The film according to this invention is multi-layers and besides the shrink base film comprises also a microwave susceptor layer, an adhesive layer for holding the surrounding layers together, and eventually a protective layer as well as a heat sealable layer.
The objective of the present invention is to find a solution for microwaveable products, wherein the distance and/or degree of and/or intensity of contact between the susceptor and the food product during microwaving is increased to obtain a better texture and other sensory attributes of the food product, with an efficient and cheaper solution than in the prior art.